Y. Narushima

Publication List Details

Period

2001 - 2008

Number

68

Co-Authors

Configuration flexibility and extended regimes in Large Helical Device (2008)

Yamada, H., Komori, A., Ohyabu, N., Kaneko, O., Kawahata, K., Watanabe, K. Y., ...

Recent experimental results in the Large Helical Device have indicated that a large pressure gradient can be formed beyond the stability criterion for the Mercier (high-n) mode. While the stability...

MHD characteristics in the high beta regime of the Large Helical Device (2008)

Sakakibara, S., Yamada, H., Watanabe, K., Narushima, Y., Toi, K., Ohdachi, S., ...

The highest volume averaged beta values beta (t) of 2.2% at B-t = 0.75 T (gas puff) and 2.4% at D-t = 1.3 T (pellet) in helical devices have been achieved in LHD. The beta (t) dependence of MHD...

Bootstrap current destabilization of ideal MHD modes in three-dimensional reactor configurations (2008)

Cooper, W. A., Margalet, S. F., Allfrey, S. J., Isaev, M. Y., Mikhailov, M. I., Shafranov, V. D., ...

In current-free stellarators, the parallel current density is normally too weak to drive global external kink modes. However, at finite values of beta, the bootstrap current (BC) can provide...

Impact of heat deposition profile on global confinement of NBI heated plasmas in the LHD (2008)

Yamada, H., Murakami, S., Yamazaki, K., Kaneko, O., Miyazawa, J., Sakamoto, R., ...

Energy confinement and heat transport of net-current-free NBI heated plasmas in the large helical device (LHD) are discussed with emphasis on density and power deposition profile dependences....

Recent advances in the LHD experiment (2008)

Motojima, O., Ohyabu, N., Komori, A., Kaneko, O., Yamada, H., Kawahata, K., ...

In the first four years of the LHD experiment, several encouraging results have emerged, the most significant of which is that MHD stability and good transport are compatible in the inward shifted...

Review on the progress of the LHD experiment (2008)

Motojima, O., Yamada, H., Komori, A., Watanabe, K. Y., Mutoh, T., Takeiri, Y., ...

Recent progress in the Large Helical Device (LHD) experiment during the last 2 yr is reviewed. The LHD has been extending its operational regime toward fusion-relevant conditions while taking...

Magnetohydrodynamic stability of free-boundary quasi-axisymmetric stellarator equilibria with finite bootstrap current (2008)

Cooper, W. A., Margalet, S. F. I., Allfrey, S. J., Kisslinger, J., Wobig, H. F. G., Narushima, Y., ...

The impact of the bootstrap current is investigated on the equilibrium properties of a two-period quasi-axisymmetric stellarator reactor with free boundary and on the corresponding ideal...

Effects of global MHD instability on operational high beta-regime in LHD (2008)

Watanabe, K. Y., Sakakibara, S., Narushima, Y., Funaba, H., Narihara, K., Tanaka, K., ...

In the Large Helical Device (LHD), the highest operational averaged beta value has been expanded from 3.2% to 4% in the last 2 years by increasing the heating capability and exploring a new magnetic...

Three-dimensional anisotropic pressure equilibria that model balanced tangential neutral beam injection effects (2008)

Cooper, W. A., Hirshman, S. P., Yamaguchi, T., Narushima, Y., Okamura, S., Sakakibara, S., ...

Fixed boundary three-dimensional anisotropic pressure equilibria are computed that are consistent with a family of distribution functions that load particles preferentially towards v parallel to...

Stability properties of anisotropic pressure stellarator plasmas with fluid and noninteractive energetic particles (2008)

Cooper, W. A., Graves, J. P., Tran, T. M., Gruber, R., Yamaguchi, T., Narushima, Y., ...

The three-dimensional (3-D) VMEC code has been modified to model an energetic species with a variant of a Bi-Maxwellian distribution function that satisfies the constraint B . del F-h = 0, and the...

Anisotropic pressure bi-Maxwellian distribution function model for three-dimensional equilibria (2008)

Cooper, W. A., Graves, J. P., Hirshman, S. P., Yamaguchi, T., Narushima, Y., Okamura, S., ...

A formulation of the anisotropic pressure magnetohydrodynamic equilibrium problem for three-dimensional plasmas with imposed nested magnetic surfaces is developed based on a bi-Maxwellian model of...

Fluid magnetohydrodynamic stabilit in a heliotron with anisotropic fast particle species (2008)

Cooper, W. A., Graves, J. P., Jucker, M., Watanabe, K. Y., Narushima, Y., Yamaguchi, T.

The local and global fluid magnetohydrodynamic stability properties of anisotropic pressure plasmas are investigated with the Kruskal-Oberman and rigid hot particle Johnson et al energy principles. A...

Overview of confinement and MHD stability in the Large Helical Device (2005)

Motojima,O., Ida,K., Watanabe,K. Y., Nagayama,Y., Komori,A., Morisaki,T., ...

This article based on the 2004 Fusion Energy Conference contributions (Vilamoura, Portugal, 1-6 November 2004)

Extension and its characteristics of ECRH plasma in the LHD (2004)

Kubo, Shin, Shimozuma, T., Yoshimura, Y., Notake, T., Idei, H., Inagaki, S., ...

One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state....

Extension and its characteristics of ECRH plasma in the LHD (2004)

Kubo, Shin, Shimozuma, T., Yoshimura, Y., Notake, T., Idei, H., Inagaki, S., ...

One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state....

Extension and its characteristics of ECRH plasma in the LHD (2004)

Kubo, Shin, Shimozuma, T., Yoshimura, Y., Notake, T., Inagaki, S., Yokoyama, M., ...

One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state....

Extension and its characteristics of ECRH plasma in the LHD (2004)

Kubo, Shin, Shimozuma, T., Yoshimura, Y., Notake, T., Inagaki, S., Yokoyama, M., ...

One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state....

Extension and its characteristics of ECRH plasma in the LHD (2004)

Kubo, Shin, Shimozuma, T., Yoshimura, Y., Notake, T., Inagaki, S., Yokoyama, M., ...

One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state....

Extension and its characteristics of ECRH plasma in the LHD (2004)

Kubo, Shin, Shimozuma, T., Yoshimura, Y., Notake, T., Inagaki, S., Yokoyama, M., ...

One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state....

Extension and its characteristics of ECRH plasma in the LHD (2004)

Kubo, Shin, Shimozuma, T., Yoshimura, Y., Notake, T., Idei, H., Inagaki, S., ...

One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state....

Extension and its characteristics of ECRH plasma in the LHD (2004)

Kubo, Shin, Shimozuma, T., Yoshimura, Y., Notake, T., Idei, H., Inagaki, S., ...

One of the main objectives of the LHD is to extend the plasma confinement database for helical systems and to demonstrate such extended plasma confinement properties to be sustained in steady state....

A demonstration of magnetic field optimization in LHD (2003)

Murakami,S., Yamada,H., Wakasa,A., Sasao,M., Isobe,M., Ozaki,T., ...

The behaviors of trapped particles in helical ripples are complicated and would enhance the radial transport of energetic particles and thermal plasma (neoclassical transport) in heliotrons. Thus the...

MHD instabilities and their effects on plasma confinement in the large helical device plasmas (2003)

Toi,K., Ohdachi,S., Yamamoto,S., Nakajima,N., Sakakibara,S., Watanabe,K. Y., ...

MHD stability of NBI heated plasmas and impacts of MHD modes on plasma confinement are intensively studied in the Large Helical Device (LHD). Three characteristic MHD instabilities were observed,...

A demonstration of magnetic field optimization in LHD (2003)

Murakami, S., Yamada, H., Wakasa, A., Sasao, M., Isobe, M., Ozaki, T., ...

The behaviors of trapped particles in helical ripples are complicated and would enhance the radial transport of energetic particles and thermal plasma (neoclassical transport) in heliotrons. Thus the...

MHD instabilities and their effects on plasma confinement in the large helical device plasmas (2003)

Toi, K., Ohdachi, S., Yamamoto, S., Nakajima, N., Sakakibara, S., Watanabe, K. Y., ...

MHD stability of NBI heated plasmas and impacts of MHD modes on plasma confinement are intensively studied in the Large Helical Device (LHD). Three characteristic MHD instabilities were observed,...

Bootstrap current destabilization of ideal MHD modes in three- dimensional reactor configurations (2002)

Cooper,W. A., Margalet,S. F., Allfrey,S. J., Isaev,M. Y., Mikhailov,M. I., Shafranov,V. D., ...

In current-free stellarators, the parallel current density is normally too weak to drive global external kink modes. However, at finite values of beta, the bootstrap current (BC) can provide...

Bootstrap current destabilization of ideal MHD modes in three- dimensional reactor configurations (2002)

Cooper, W. A., Margalet, S. F., Allfrey, S. J., Isaev, M. Y., Mikhailov, M. I., Shafranov, V. D., ...

In current-free stellarators, the parallel current density is normally too weak to drive global external kink modes. However, at finite values of beta, the bootstrap current (BC) can provide...